Post #2549924

Musings on Arctic permafrost. The thaw is going to release ancient carbon. Depending how hot we let it get, low anthropogenic emissions less so, high levels let the release continue for centuries to come. See chapter 4 https://iccinet.org/statecryo24/ But I'm thinking: what is permafrost? It's an ancient swamp, a bog. And thawing the bog also revives the bog processes. So we're concerned about carbon release in form of microbes burping #methane while they're feasting on the old, dead plant material below the "water" surface. But what about the other bog property, the one that hides new plant material under water = burying contemporary carbon? It's a near-permanent drawdown of CO2. Just think about the well-preserved corpses archaeologists examine for clues on cultures thousands of years ago. That's ancient CO2, safely hidden away from the atmosphere. And Arctic permafrost is becoming such a bog again. Yes, the methane release from microbes is bad. But as long as thawed Arctic permafrost doesn't dry up, CO2 drawdown will occur as well, and in a place where it hadn't occurred before. Luckily, CMIP6 sees a considerable, continuous rise in precipitation for the Eurasian permafrost region https://climatereanalyzer.org/research_tools/monthly_tseries/ So the new, huge bog is not at risk of drying out. And some water from the thaw is also going to stay in the soil. From what I read about permafrost so far, I do not recall that a number is put on the likely CO2-storage dynamics. Only methane release from permafrost thaw receives numbers. Pretty big numbers, too. Depending on human emissions, 300-500 Gt CO2-eq per century, see the link above. = +0.2 to 0.3 °C per century, (short-term heating from actual methane is higher). But from lengthy discussions on Twix a few years ago, I recall that wetland/peat researchers aren't at all concerned about renewed methane emissions during re-wetting of dried wetlands elsewhere. They argue that the expected new CO2 drawdown, plus ending CO2 emissions from the dried-out wetland (globally 2Gt CO2 / year), outweighs the heating impacts of methane production. To my unlearned mind, when I transfer this assessment to new bog activity in the permafrost region, the thaw would even be a reason for re-joicing... 😱 😁 🖖🏽 #Arctic #permafrost #methane #CH4 #ClimateChange